Process of producing a soluble potassium compound.



nuns. mssnzr'r, or CATONSVILLE, MARYLAND, ASfiIGrNOLR *ro was sra'n o'HEMIc L COMPANY, OF BALTIMORE, MARYLAND, A conrona'rion 0F MARYLANLP.

- rnoonss or rnonnome A SOLUBLE POTASSIUM coiirouni).

1,217,388.. No Drawing.

To all whom it may concern I Be it, known that I, HARRY P. B ssn'r'r, a citizen of the United States, residing at Catonsville, in the county of Baltimore and State of Maryland, have invented certain new and useful Improvements in Processes of Producing a Soluble Potassium "Cour pound, of which the following is a specification. y

This invention relates to processes of producing water soluble potassium salts from materials containing 1 insoluble potassium salts, such for example asfeldspathio rock, green sand marl and the like, in order'to separate or'recover potash or potassium salts therefrom, and has particular reference to 'certain improvements in processes of decomposin the potassium containing alkali s1l1- cates y means of sodium acid sulfate; one

improvement consisting in so proportioning the. sodium acid sulfate to the insoluble alkaline silicate that'radical and important resultsin respect of lowering the cost of the resulting potassium product are effected and -asecond improvement consisting in the employment with the alkali silicate, of an agent 'or reagent adapted to absorb sulfuric acid, or more properly,'sulfur trioxid which is liberated duringthe reaction which occurs in the process referred'to.

Other'objects and advantages will beapparent in thecourse-ofthe following speci- In' decomposing insoluble potassium con taining 'alkali metal silicates by means of sodiumacid sulfate, or such sulfate and a reducing-agent, I havefound that the yield of soluble potassium salts is'very materially increased if the reaction is carried out in.

i it appears thatthis improved yield of soluble potassium salt or salts results from the absorbent action'of the reagent employed whereby the sulfur trioxid is brought more intimately into, and maintained for a longer time in,-contact with the silicate to be decomp osed. I

. I employigreen sand marl (glauconit'e) although pulverized feldspar' may beadvanvtageously used. 7 It is advantageous togrind the material to pass throughfa twenty mesh sieve and better results are obtained-if it ,is

fipecification ofletters Eatent.

Application mantra aims. Serial at. 12,932.

6 Patented Feb. 27, 1917.

ground to forty or'siXty mesh, although the 7' expense of further grinding may more than compensate for the advantage resulting from the additional fineness of the material under treatment. The insoluble potassium silicate is mixed with sodium acid sulfate in any proportions desired although'I greatly prefer to. mix the insoluble silicate with a materially smaller amount by' weiglit of the acid sulfate, preferable with from approximately onehalf to three fourths by weight of the acid sulfate. To this may be advantageously added a reducing agent such as coke in approximately from one to three I I per cent. by weight of the mixture. I have obtained the best results by mixing the silicats and acid sulfate in the following proportions by weight;

Potassium containing silicate--- 2000 parts.

Sodium acid sulfate 1500 parts. To the mixture I may advantageously add.

the sulfur trioxid absorbing agent which, in,

the case of water which I prefer to use, is

added in such quantity that when the mixture is squeezed in the hand it will retain the shape given to it. I have obtained the best results by adding Water in the. proportions of from 20 to 25 per cent. by weight furnace or the like at a red heat, the pre ferred temperature being approximately;

from 900 to 1000 F. Instead of adding- Water to the mixture, the Whole or a part so tu're being furnaced, preferably in a tube of the water may be added as steam during the heating operation but the cooling effect of the steam is such, that it is ordinarily not advisable to introduce more than a fourth to a half of the water required in this wayaioo Coke maybe added to the mixture before furnacing it or the mixture may -be advantageously subjected to the action of a I I reducing flame while being furnaced. In the preferred practiceof my process,-

of the insoluble potassium containing siliwater, Whereby'the portion ofthe mixture near the end'of the progressive heating is,

cate, acid sulfate decomposable'by heatand which dried and heated to a reacting temperature for ircducinfz sulfur trioxid by the decomposifion of the acid sulfate, and conduct the sulfur trioxid thus produced into contact with the portion of the mixture near the beginning of the progressive heating and portion contains the water, so that the sulfur trioxid is absorbed by the water.

After heating the mixture to a reacting temperature as described the resulting fused mass is allowed to cool and leached with water. The leaching operation results in the production of a solution containing sodium and potassium sulfates which may e separated by any suitable process such for example, as my process described and claimed in Patent No. 1,091,033, granted While I ha \e described in detail the preferred embodiment of my process and the proportions of ingredients, it is to be understood that the details of procedure and proportions of reagents may be varied and that known chemical equivalents of the materials may be employed without departure from the spirit of my invention or the scope of the subjoined claims.

n a copending application, Serial No. 40,031 filed July .15, 1915 for process of pro ducing potassium salts I have described and claimed a process of heating to a reacting temperature a potassium containing silicate, a metal sulfate, a reducing agent and sulfuric acid, and such process isnot specifically claimed herein. In the copending application Serial No. 40,031, I employ an alkaline earth metal sulfate, namely, calcium sulfate, while in the present application I employ sodium acid sulfate.

ai-ing described my invention, I claim The herein described process of obtaining soluble potassium salts, which consists in progressively heating a mixture of an insoluble potassium containing silicate, an acid sulfate decomposable by heat, and a sulfur trioxid absorption agent, whereby themixture near the end of the progressive heating is heated to a reaction temperature for probeginning of the progressive heating, so that the sulfur trioxid 1S absorbed by the sulfur 2. The herein described process of obtaining soluble potassium salts which consists in progressively heating a mixture of an insoluble potassium. containing silicate, an acid heat, a reducing agent, and a. sulfur trioxid absorption agent, whereby the port. or of the mixture near the end of the progressive heating is dried and heated to a reaction temperature and sulfur trioxid produced by the decomposition of the acid sulfate, aid conducting the sulfur tri- -of the progressive heating oxid thus produced into contact with the portion of the mixture near the beginning and which con- :lbSOlPtlOll agent, so is absorbed by such tains the sulfur trioxid that the sulfur trioxid agent.

The herein. described process of obtaining soluble potassium salts, which consists in progiessively heating a mixture of an insoluble potassium containing silicate, an acid sulfate decomposable by heat, and water, whereby the portion of the mixturenear the end of the progressive heating is dried and heated to a reaction temperature for producing sulfur trioxid by the decomposition of the acid sulfate. and conducting the sulfur trioxid thus produced into contact with the portion of the mixture near the. beginning of the progressive heating and which contains the water, so that the sulfur trioxid is absorbed by the water.

-l. The herein described process of obtaining soluble potassium salts, which consists in progressively heating a mixture containing an insoluble potassium containing silicate, an alkali metal acid sulfate and a sulfur trioxid absorption agent, whereby the portion of the mixture near the end of the progressive heating is heated to a reaction temperature and sulfur trioxid produced by the decomposition of the alkali metal acid sulfate, and conducting the sulfur trioxid thus produccd into contactwith the portion of the mixture near the beginning of the progressive heating and which contains the sulfur trioxid absorption agent, so that the sulfur trioxid is absorbed by such agent.

5. The herein described process of obtaining soluble potassium salts, which consists in progressively heating an insoluble pota :sium silicate and an alkali presence of a sulfur trioxid absorption agent and a reducing agent, whereby the portion of the mass near the end of the progressive heating s heated to a reaction temperature and sulfur trioxid produced by the decomposition of the alkali metal acid sulfate, and conducting the sulfur trioxid thus produced into contact with the portion of the mass near the beginning of the progressive heating and which contains the sulfur trioxid absorption agent, so that the sulfur trioxid is absorbed by the sulfur trioxid absorption agent.

soluble potasa reaction temperature for'producing sulfur trioxid composition 0 he pr ggrescontact with the portion of the i 130 by the desive heating and which contains the Water,

so that the sulfur trioxid is absorbed by the Water. v

7. The herein described process of obta1ning soluble potassium salts, which consists in terially smaller amount by Weight of sodium acid sulfate, and a sulfur tridxid absorption agent, whereby the portion of the mixture near the end of the progressive heating is heated to a reaction temperature for producing sulfur trioxid by the decomposition o the sodium acid sulfate, and conducting t esulfur trioxid thus produced into contact with the portion of the mixture near the beginning of the progressive heating and Which contains the sulfur trioxid absorption agent, so that the sulfur trioxid is, absorbed by such agent.

8; The process of recovering potash from green sand marl, feldspar, or other potassium silicate wherein potassium is present in an insoluble form, Which consists in progressivelyheating. a mixture of a potassium containing silicate and sodium acid sulfate in the presence of Water, whereby the portion of the mixture near the end of the progressive heating is heated to a reaction tempera- .ture for producing sulfur trioxid by the decomposition of the sodium acid sulfate, and causing the sulfur trioxid thus produced to contact with the portion of the mixture near the beginning of the progressive heating and which contains the water, so that the sulfur trioxid is absorbed by the Water, and separating the soluble portion from the remaining portion of the resulting mixture.

In testimony whereof I afiix my signature in presence of two witnesses.

HARRY P. BASSETT. Witnesses: I

PH; H. HOFFMAN, G. H. SLATER. 

